ABSTRACT
Objective:To evaluate the left ventricular diastolic dyssynchrony (LVDD) and its influencing factors early after acute myocardial infarction (AMI) using phase analysis of SPECT gated myocardial perfusion imaging (GMPI).Methods:Bama miniature swines ( n=16) were subjected to establish AMI models. GMPI was performed before and 1 d after AMI to obtain the extent of myocardial perfusion defect (Extent, %) and left ventricular systolic dyssynchrony (LVSD)/LVDD parameters, namely the phase histogram bandwidth (PBW) and phase standard deviation (PSD). Meanwhile, left ventricular end-diastolic volume (LVEDV), left ventricular end-systolic volume (LVESV), left ventricular ejection fraction (LVEF), and the ratio of early to late peak mitral diastolic flow (E/A) were obtained by echocardiography. Independent-sample t test, paired t test and Pearson correlation analysis were used to analyze the data. Results:Sixteen AMI swines were successfully created. Compared to baseline, Extent, LVEDV and LVESV significantly increased on 1 d after AMI ( t values: -11.14, -4.55, -6.12, all P<0.001), while LVEF and E/A significantly decreased ( t values: 10.16, 2.18, P<0.001, P=0.046). GMPI showed that the LVDD parameters PBW and PSD increased significantly on 1 d after AMI when compared to those at baseline((142.25±72.06)° vs (33.06±8.98)°, (56.15±26.71)° vs (12.51±5.13)°; t values: -6.11, -6.60, both P<0.001). There were significant differences between LVSD parameters and LVDD parameters (PBW: (109.06±62.40)° vs (142.25±72.06)°, PSD: (44.40±25.61)° vs (56.15±26.71)°; t values: -2.73, -2.20, P values: 0.016, 0.044). LVDD parameters PBW, PSD were negatively correlated with E/A after AMI ( r values: -0.569, -0.566, P values: 0.021, 0.022), and positively correlated with the Extent ( r values: 0.717, 0.634, P values: 0.002, 0.008). The phase analysis of SPECT GMPI to evaluate LVDD showed good intra-observer and inter-observe reproducibility (intraclass correlation coefficient (ICC): 0.953-0.984, all P<0.001). Conclusions:LVDD occurs early on 1 d after AMI, and can reflect left ventricular diastolic dysfunction. The Extent is correlated with LVDD significantly. Phase analysis of SPECT GMPI is an accurate method to evaluate LVDD and left ventricular diastolic function.
ABSTRACT
Objective:To investigate the predictive value of 18F-fluorodeoxyglucose (FDG) PET/CT metabolic parameters for occult lymph node metastasis (OLM) in non-small cell lung cancer (NSCLC). Methods:A total of 183 patients (72 males, 111 females; age (61.5±8.4) years) who underwent 18F-FDG PET/CT and preoperatively diagnosed with clinical N0 stage (cN0) in Third Affiliated Hospital of Soochow University from January 2013 to December 2018 were retrospectively enrolled. All patients underwent anatomical pulmonary resection with systematic lymph node dissections within 3 weeks after 18F-FDG PET/CT examinations. According to the presence or absence of lymph node metastasis, patients were divided into OLM positive (OLM+ ) group and OLM negative (OLM-) group. Parameters of primary lesions, such as the maximum diameter (D max), tumor sites, morphological features, maximum standardized uptake value (SUV max), mean standardized uptake value (SUV mean), metabolic total volume (MTV), total lesion glycolysis (TLG), tumor SUV max to liver SUV mean (TLR max), tumor TLG to liver SUV mean (TLR TLG) were analyzed. Mann-Whitney U test and χ2 test were used to compare the parameters between groups. Multivariable logistic regression was used to analyze the independent risk factors for OLM. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic value of different parameters. Results:Among 183 patients, 25 (13.7%, 25/183) of them were diagnosed as OLM. In OLM+ group, 46 lymph nodes were pathologically positive for metastasis, including 15 N1 disease and 31 N2 disease. D max (2.9(2.3, 3.7) vs 2.3(1.7, 2.8) cm), lobulation ((76.0%(19/25) vs 37.3%(59/158)), SUV max (11.1(7.9, 17.7) vs 4.7(2.3, 9.2)), TLG (41.5(10.2, 91.1) vs 15.6(6.5, 23.8) ml), TLR max (4.7(3.5, 7.6) vs 2.1(0.9, 4.0)) and TLR TLG (18.1(5.0, 44.3) vs 6.1(3.0, 11.4) ml) of the primary lesions in OLM+ group were significantly higher than those in OLM-group ( z values: from -4.709 to -3.247, χ2=13.190, all P<0.05). Multivariable logistic regression analysis showed that TLR max (odds ratio ( OR)=15.145, 95% CI: 3.381-67.830, P<0.001) and D max ( OR=3.220, 95% CI: 1.192-8.701, P=0.021) were independent risk factors for OLM. TLR max yielded the highest area under curve (AUC; AUC=0.794) with the threshold of 3.12, and the sensitivity, specificity, accuracy, positive predictive value and negative predictive value for predicting OLM were 92.0%(23/25), 63.3%(100/158), 67.2%(123/183), 28.4%(23/81) and 98.0%(100/102), respectively. Conclusions:TLR max of tumor is the independent risk factor for OLM in NSCLC patients. TLR max can sensitively predict OLM preoperatively in patients with NSCLC.